This invention relates to fabric knit from non-elastic yarns and elastic yarns. More particularly, it relates to sweater knit fabric made from hard yarn plaited with bare elastomeric yarn.
Knit fabrics constructed by plaiting hard yarns, such as nylon, wool, cotton and polyester, with processed elastomeric yarns, such as core spun elastomeric yarn, covered elastomeric yarn, or taslanized elastomeric yarn, are well known. Such fabrics are typically prepared by either knitting the two yarns together, or by plaiting the elastomeric yarn and the knitted structure formed by the hard yarn. Processed elastomeric yarns are less than desirable for use in sweater and other knit outerwear since they are expensive to prepare and involve difficulties in subsequent garment manufacture, such as color grin-through, irregular stitch formation, and excessive weight.
Knit fabrics constructed by plaiting hard yarn with bare elastomeric yarn, such as spandex, are known, and overcome some of the above problems. However, such constructions, when knit by known prior art methods, result in knit fabrics that exhibit a number of undesirable conditions, such as broken spandex filaments, barre', unequal selvedge lengths, and stitch jamming. This, in turn, results in lower quality knit fabric and waste. Moreover, any variation in the speed of the fed spandex yarn will induce variation in both spandex yarn tension and draft, resulting in changes in dimension of the finished garment blank.
In European Publication No. 0119536 owned by Bayer AG of Germany, there is described a method of knitting together spandex yarn with hard yarn in which the feeding of spandex yarn is controlled by means of a friction based tension device, which operates to frictionally restrain the fed spandex yarn. The method described in this publication is disadvantageous because tension of the fed yarn is extremely difficult to control uniformly--the yarn is intermittently grabbed and released as it is being fed for knitting. This leads to uneven and irregular loop formation and fabric width in the end product that is produced by this method.
Accordingly, it would be desirable to provide a method and system which overcomes the disadvantages found in the prior art.